#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main()
{
	int arr[] = {1,2,3,4,6,4,1};
	int sz = sizeof(arr) / sizeof(arr[0]);
	int i = 0;
	for (i = 0; i < sz; i++)
	{
		if (arr[i] != 0)
		{
			int j = 0;
			for (j = i + 1; j < sz; j++)
			{
				if (arr[i] == arr[j])
				{
					arr[i] = 0;
					arr[j] = 0;
					break;
				}
				else if (j == sz - 1)
				{
					printf("%d ", arr[i]);
					break;
				}
			}
		}
	}
	return 0;
}